Residual Calculation Of TDICCD Space Camera For Whiskbroom Of Image Motion Velocity Matching

Wide field, high resolution imaging are the two imaging indexes of TDICCD space camera nowadays. The accurate image motion compensation is the key to keep the imaging quality of TDICCD space camera good. To ensure the wide field under the high resolution imaging, on the basis of the homogeneous coordinate transformation, it establishes the model of TDICCD space camera for whiskbroom of image motion velocity, uses the Monte Carlo method to get the image motion velocity error and uses MTF to assess the image quality. Finally, according to the current technical level and the results of the simulation, it predicts the angular velocity residuals which caused by the others factors of the pendulum mirror to make up the defects of the model. The specific work of this paper includes:Firstly, it introduces rotation, translation, scaling matrix of the homogeneous coordinate transformation and reflector matrix of the pendulum mirror. It defines each coordinate system of the imaging process and establishes the model of TDICCD space camera for whiskbroom of image motion velocity by combining the reflector matrix of the pendulum mirror and gives the formula of the imagining velocity and drift angle which gets ready for later experiment simulation.Secondly, referring on a camera’s parameters, it uses the pushbroom and whiskbroom model to verify the correctness of the whiskbroom model according to the imaging model. By setting the angular velocity of the swing mirror reasonably,it can carry on scanning imaging across the direction of navigation when it flies along the direction of navigation, which achieves a large field of view, wide swath imaging, verifying the validity of the model.Then, it carries out the error distribution of the orbit attitude parameters which affect the image motion velocity vector, uses Monte Carlo to integrate the distribution error to get the imaging motion velocity residual. Based on the same orbit and attitude parameter error, it combines the different angular velocity error of pendulum mirror, and uses MTF to evaluate the imaging quality which degraded by the residual. The result shows that based on the same orbit and attitude parameter error, the smaller the angular velocity of the pendulum mirror is, the smaller the image motion velocity residuals is, the higher the imaging quality is.Finally, in the existing technical level, it predicts the angular velocity of the pendulum mirror with the method of threshold setting which solve the problems in the model that caused by the existing technical level, keeping the imaging quality good, and the model valid.